Sockets are known for containing carriers of integrated circuit (IC) chips having for example 68 contact locations and electrically connecting the conductors of the carriers to circuit panels to which the sockets are mounted, thus electrically interconnecting the 68 contacts of the IC to the circuit panel. Power current for the IC conventionally is transmitted from a remote power source by way of selected conductors of the circuit panel through usually a plurality of terminals of the socket and carrier to circuit paths of the chip. In many applications it is critical to the proper functioning of the electronic apparatus within which the circuit chip is mounted, that the chip maintain memory of the information stored therein. It is desired that there be an absolute continuity of sufficient electrical power supplied to the IC chip at all times, to maintain memory. A random access memory (RAM) is characterized as being volatile when it has no internal memory protection against power failure, with continuous power necessary to maintain the integrity of the data stored therein.
Products are known recently in which a volatile RAM is contained in a dual-in-line package (DIP) which also integrally contains a lithium energy source, or battery, to assure a continuous power source and provide a nonvolatile RAM module package. The module package also includes a control circuit for the battery which constantly monitors primary power input (such as plus five volts) for an out of tolerance condition, such as Part No. DS1220 sold by Dallas Semiconductor Corporation of Dallas, Texas. In such a condition the control circuit switches on the lithium energy source to continue a necessary threshold of power, protects against garbled data, and also maintains the data in the absence of primary power for up to ten years, all without additional support circuitry. Upon resumption of at least threshold primary power, the lithium energy source is disconnected and the RAM module operates at low power until full primary power is restored.
Products are also known which are DIP-style sockets matable with a volatile RAM and which contain an embedded lithium energy source and a built-in CMOS (complementary metal oxide semiconductor) controller circuit. Such a socket monitors the voltage of the incoming primary power, detects an out-of-tolerance condition, and switches on the internal lithium energy source to provide write protection and prevent garbled data. Two similar such products are "SmartSockets" sold by Dallas Semiconductor Corporation, Dallas, Texas under Part No. DS1213 and Part No. DS1213C. Each of these two products includes two lithium energy sources each of, for example, 35 mA-hrs (millampere-hours) and a control circuit which performs five circuit functions required in order to provide battery back-up capability to a CMOS memory: a switch to direct power either from the primary power supplied via the printed circuit panel or the back-up battery; power fail detection using a precision comparator; checking battery status; battery redundancy with an internal isolation switch using two batteries to insure reliability and using the battery with higher voltage; and, providing "write protection" by holding the "chip enable" signal to the memory module to within a fixed voltage deviation from nominal for power, or if the "chip enable" signal is active at point of failure meaning that a byte of data is in the process of being entered into the memory at the moment of power failure, delaying passing through the "write protection" signal to the memory module until the memory cycle is complete to avoid corrupting the data meaning that the subject byte of data has been entered with integrity. The products include adapter boards comprising conventionally fabricated printed circuit board elements containing etched circuitry and conventional plated through-holes to which are mounted and electrically connected the energy sources and logic means, all of which is then conventionally potted or overmolded.
Other similar products also sold by Dallas Semiconductor include a battery manager, having Part No. DS1259 to which a battery can be connected to supply power to CMOS electronic circuits when primary power is lost, especially for use in portable and nonvolatile electronic equipment. Additionally Part No. DS1260 is a lithium energy source of for example 1000 mA-hrs for a system of memory modules, sold under the designation "SmartBattery," which includes an integral control circuit monitoring the primary power to detect out-of-tolerance conditions, switching on the battery to supplant the primary power when necessary, and checking the level of reserve power in the battery and signaling upon detecting significant decline.
It is desired to provide an adapter for an IC chip carrier socket which upon mounting between the printed circuit panel and the socket, interrupts selected circuit paths between the socket and the printed circuit panel to which it is electrically connected, to interpose electrical components between the IC chip mounted into the socket and the panel to modify or affect or respond to selected transmissions along the selected circuit paths without affecting transmissions along the nonselected circuit paths which are passed through the adapter without being affected.
It is desired to provide such an adapter which easily carries the respective electrical component or components with minimum bulk or occupation of panel real estate.
It is desired to provide an adapter for a volatile IC chip assembled within a carrier socket assembly which assures continued sufficient power to the IC chip substantially without requiring modification of the IC carrier socket assembly.
It is desired to provide such an adapter which is a low height integral assembly placeable between the socket and the printed circuit panel and occupying a minimum of bulk space and a minimum of printed circuit panel real estate.
It is desired to provide such an adapter which is easily and inexpensively manufacturable, easily handled, and easily and economically replaceable.
It is desired to provide such an adapter containing an energy source and a control circuit therefor which do not interfere with the electrical connection of pass-through non-power circuits thus minimizing possible signal degradation or slowing the speed of signal transmission.
It is also desired to provide an adapter containing one or more plated blind holes as distinguished from and in addition to plated through-holes for interrupted circuit paths.
It is further desired to provide an adapter which includes features such as dual-diameter through-holes, standoff bosses and boss-receiving apertures, component-receiving recesses, and lead-in features facilitating post insertion, or which enables insert molding of contact elements thereinto.